In an AOC (Active Optical Cable) for an active HDMI (High Definition Multimedia Interface), a DisplayPort, a DVI (Digital Video Interface), etc. which are recently rapidly increasing in demand, there is the need for an optical module of four channels or more which focuses four wavelengths on a single optical fiber to transmit A/V (Audio/Video) data. Most AOC cables on the market have a structure using four or two optical fibers. However, the AOC cables having such a structure are disadvantageous in that installation, maintenance, and repair are difficult. These problems may be exacerbated in long-distance transmission.